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Nielsen expands Four-Screen Ad Deduplication across CTV in Japan

3 minute read | August 2026

Media buyers and sellers can now compare deduplicated campaign reach across computer, mobile, connected TV and linear TV across all measurable CTV publishers in Nielsen ONE Ads

Tokyo, Japan, August 3, 2026 – Nielsen, a global leader in audience measurement, data and media intelligence, today announced the expansion of its Four-Screen Ad Deduplication measurement in Japan to include all measurable connected TV inventory available through Nielsen ONE Ads.

The enhancement builds on Nielsen’s Four-Screen Ad Deduplication capability launched in Japan in June this year, which initially measured YouTube campaigns across computer, mobile and connected TV alongside linear TV.

With this latest update, measurement is no longer limited to YouTube CTV inventory. Media buyers and sellers can now understand deduplicated reach across computer, mobile, connected TV and linear TV for campaigns running across all other measurable Nielsen ONE Ads CTV inventory.

The expanded capability enables advertisers, agencies and media owners to compare the combined reach of campaigns across computer, mobile and CTV with linear television, providing a more complete view of how audiences are reached across platforms and publishers.

Matty Lin, Nielsen’s APAC Regional Sales Leader, said: “Advertisers in Japan are increasingly planning campaigns across linear television, digital video and connected TV as part of one audience strategy. Expanding Four-Screen Ad Deduplication across measurable CTV inventory gives the industry a clearer view of total campaign reach, frequency and incremental audiences, without being limited to a single publisher.

“This is an important step towards true cross-media measurement through Nielsen ONE. By bringing more measurable inventory into a consistent and independent measurement framework, Nielsen is helping media buyers and sellers make better-informed decisions about where to invest, how to manage frequency and how effectively their campaigns are reaching audiences across screens.”

The expanded reporting includes metrics such as unique audience, audience reach, average frequency, and gross rating points. Co-viewing is also included in total impression delivery for clients assessing tracked-ad performance.

Data will initially be delivered through offline reporting, with no forced campaign splits required as part of the update.

For active campaigns already enabled for Nielsen measurement, clients will need to ensure the relevant CTV publisher inventory has also been activated for measurement. Additional action may be required where measurement has not yet been enabled for newly included inventory.

The expansion moves Nielsen ONE Ads closer to the complete inclusion of all measurable inventory, supporting Nielsen’s goal of delivering trusted, deduplicated and comparable measurement across platforms.

About Nielsen

Nielsen is a global leader in audience measurement, data and analytics. Through our understanding of people and their behaviors across all channels and platforms, we empower our clients with independent and actionable intelligence so they can connect and engage with their global audiences – now and into the future. Learn more at www.nielsen.com and connect with us on social media (X, LinkedIn, YouTube, Facebook and Instagram).

Media Contact

Dan Chapman

Assoc. Director, Communications, Nielsen APAC

dan.chapman@nielsen.com

+61 404 088 462